Grandmaster Di would definitely be famous. However, if he died, there was no meaning for a dead person becoming famous.
Even if he failed in the three challenges, it wouldn't have affected his rise to fame. But what if he was dead? He consecutively killed two grandmasters from the Yan Clan and the hatred between both sides was set in stone. The Yan Clan would kill him for sure. Hence, for the last challenge round, Di Tian would surely be defeated because the Yan Clan would surely send out someone far above his league to crush him.
Before Di Tian challenged the Yan Clan, no one would have expected such an ending. Even the Yan Clan didn't imagine this. If not, they wouldn't have reacted like that, even allowing Di Tian to enter. After today, the name of their Yan Clan would surely become a joke in the eyes of others.